<?php

/**
 * @author Martin Dougiamas
 * @license http://www.gnu.org/copyleft/gpl.html GNU Public License
 * @package moodle multiauth
 *
 * Authentication Plugin: POP3 Authentication
 *
 * Authenticates against a POP3 server.
 *
 * 2006-08-31  File created.
 */

if (!defined('MOODLE_INTERNAL')) {
	die('Direct access to this script is forbidden.');	///  It must be included from a Moodle page
}

require_once($CFG->libdir.'/authlib.php');

/**
 * POP3 authentication plugin.
 */
class auth_plugin_pop3 extends auth_plugin_base {

	/**
	 * Constructor.
	 */
	function auth_plugin_pop3() {
		$this->authtype = 'pop3';
		$this->config = get_config('auth/pop3');
	}

	/**
	 * Returns true if the username and password work and false if they are
	 * wrong or don't exist.
	 *
	 * @param string $username The username (with system magic quotes)
	 * @param string $password The password (with system magic quotes)
	 * @return bool Authentication success or failure.
	 */
	function user_login($username, $password) {
		if (! function_exists('imap_open')) {
			print_error('auth_pop3notinstalled','auth');
			exit;
		}

		global $CFG;
		$hosts = split(';', $this->config->host);   // Could be multiple hosts
		foreach ($hosts as $host) {				 // Try each host in turn
			$host = trim($host);

			// remove any trailing slash
			if (substr($host, -1) == '/') {
				$host = substr($host, 0, strlen($host) - 1);
			}

			switch ($this->config->type) {
				case 'pop3':
					$host = '{'.$host.":{$this->config->port}/pop3}{$this->config->mailbox}";
				break;

				case 'pop3notls':
					$host = '{'.$host.":{$this->config->port}/pop3/notls}{$this->config->mailbox}";
				break;

				case 'pop3cert':
					$host = '{'.$host.":{$this->config->port}/pop3/ssl/novalidate-cert}{$this->config->mailbox}";
				break;
			}

			error_reporting(0);
			$connection = imap_open($host, stripslashes($username), stripslashes($password));
			error_reporting($CFG->debug);

			if ($connection) {
				imap_close($connection);
				return true;
			}
		}
		return false;  // No matches found
	}

	/**
	 * Returns true if this authentication plugin is 'internal'.
	 *
	 * @return bool
	 */
	function is_internal() {
		return false;
	}

	/**
	 * Returns true if this authentication plugin can change the user's
	 * password.
	 *
	 * @return bool
	 */
	function can_change_password() {
		return !empty($this->config->changepasswordurl);
	}

	/**
	 * Returns the URL for changing the user's pw, or false if the default can
	 * be used.
	 *
	 * @return bool
	 */
	function change_password_url() {
		return $this->config->changepasswordurl;
	}

	/**
	 * Prints a form for configuring this authentication plugin.
	 *
	 * This function is called from admin/auth.php, and outputs a full page with
	 * a form for configuring this plugin.
	 *
	 * @param array $page An object containing all the data for this page.
	 */
	function config_form($config, $err, $user_fields) {
		include "config.html";
	}

	/**
	 * Processes and stores configuration data for this authentication plugin.
	 */
	function process_config($config) {
		// set to defaults if undefined
		if (!isset ($config->host)) {
			$config->host = '127.0.0.1';
		}
		if (!isset ($config->type)) {
			$config->type = 'pop3notls';
		}
		if (!isset ($config->port)) {
			$config->port = '143';
		}
		if (!isset ($config->mailbox)) {
			$config->mailbox = 'INBOX';
		}
		if (!isset($config->changepasswordurl)) {
			$config->changepasswordurl = '';
		}

		// save settings
		set_config('host',	$config->host,	'auth/pop3');
		set_config('type',	$config->type,	'auth/pop3');
		set_config('port',	$config->port,	'auth/pop3');
		set_config('mailbox', $config->mailbox, 'auth/pop3');
		set_config('changepasswordurl', $config->changepasswordurl, 'auth/pop3');

		return true;
	}

}

?>
